Cardiac Medicine Certification (CMC) Practice Exam

How is ventricular tachycardia characterized?

1. Heart rate between 60 and 100 bpm

2. Multiple PVCs at a rate of 100 to 250 bpm

3. Regular p-wave to QRS ratio

4. Presence of sinus bradycardia

The correct answer is: Multiple PVCs at a rate of 100 to 250 bpm

Ventricular tachycardia is characterized primarily by the presence of multiple premature ventricular contractions (PVCs) occurring at a rapid rate, specifically between 100 and 250 beats per minute. This arrhythmia originates from the ventricles, and the rapid firing of the ventricular ectopic pacemakers leads to this elevated heart rate. The distinguishing feature of ventricular tachycardia is that it often has a wide QRS complex, reflecting the abnormal conduction pathway through the ventricles due to the ectopic focus. When observing patients with this tachycardia, one may notice that the rhythm is typically regular, and the QRS complexes are usually wider than those seen in normal sinus rhythm. In contrast, the other options provided do not accurately represent ventricular tachycardia. A heart rate between 60 and 100 beats per minute indicates a normal sinus rhythm rather than tachycardia. The regular p-wave to QRS ratio is typically present in normal rhythms but is absent in ventricular tachycardia, where atrial activity may be dissociated from ventricular contractions. Lastly, sinus bradycardia signifies a slower than normal heart rate, which is the opposite of what is seen in ventricular tachycardia. Therefore,